Minecraft on his WhatsApp channel just posted the following:

A picture of Alex mining in a "normal" cave. But the strange thing about this is that in the caption of the image it has written "C u soon" And analyzing the image and the text, we can assume that he is talking about copper. In the periodic table it is found as Cu, and the text just makes a little play on words. Besides, can we say that yes, they're talking about copper, Alex in a cave, and a pun about copper? Many coincidences.

Mojang is making references to this on other social media. What do you think? Do you think the next one will be about copper? Maybe it'll be the return of the copper golem?